Heating and overheating are serious issues for electronics. In general, as electronics heat up, leakage currents increase, thermal noise increases, dopants may migrate, and/or the crystalline structure of silicon components may break down. This can lead to malfunctioning components or a complete device failure. In addition, electronics at higher temperatures tend to require more power to operate.
This problem particularly acute in vehicle electronics systems, particularly those in or near the engine compartment, which tend to be exposed to high temperatures. Thus, cooling for these electronics is of particular importance.
Another problem in vehicle systems relates to the air conditioning system. Most vehicle air conditioning systems function by converting a refrigerant between vapor and liquid forms using a compressor. However, as the refrigerant is typically circulated around a closed-circuit loop, it is possible that liquid refrigerant can enter, and damage, the compressor. Therefore, an accumulator, or other liquid-gas separator device, is sometimes used to store or accumulate liquid refrigerant and prevent it from entering the compressor. By doing so, the accumulator helps prevent liquid refrigerant from entering the compressor. Over time, however, too much liquid refrigerant may accumulate in the liquid-gas separator device.
Another problem relates to air conditioning systems (and heating, ventilation, and air conditioning (HVAC) systems) having multiple compressors. When switching between compressors there is a risk of backflow of refrigerant in the system. This backflow of refrigerant may prevent components of the air conditioning system from operating and/or may damage the components. For example, in a vehicular air conditioning system with a primary engine-driven compressor and a secondary electrically-driven compressor, the primary compressor may be capable of operating at higher pressures than the secondary compressor. Thus, in this example, when switching from the primary compressor to the secondary compressor, the pressure may initially exceed the secondary compressor's operating abilities. This may prevent the secondary compressor from starting and may lead to backflow in the system, which could damage of the secondary compressor and other components.